# The barium-yttrium ceramic compound used to demonstrate superconductivity will work only if supercooled to a temperature of 125 K. What is the equivalent temperature in °C and in °F?

Jan 29, 2016

125 K = $- 148.17$ $\text{^0"C}$
$= - 234.67$ $\text{^0"F}$

#### Explanation:

The two temperature scales Celsius and Fahrenheit are based on the freezing point and boiling point of water (at standard temperature and pressure) as two extremities, as shown in the picture.

The Celsius scale starts from zero and goes up to 100, the total interval being divided into 100 equal divisions. Earlier it was called Centigrade scale. Later on the name was changed in honour of a scientist who developed a similar scale. All countries who follow SI system of units use this scale with the exception of USA and few other nations.

The Fahrenheit scale starts from 32 and goes up to 212, thus the interval between two points is equally divided in to 180 parts.

[montereyinstitute.org]

The third scale Kelvin, named after the scientist Lord Kelvin who calculated the temperature 'Absolute Zero'. This is the point at which all thermal motion cease to exist. Theoretically it has been calculated to be equal to $- 273 \text{^0"C}$. Which makes freezing point of water equal to 273 K. (For precise measurements it is taken as 273.15 K)

Conversion formulae between the three scales are as follows.

$\frac{\text{^0"C")/100=(""^0"F} - 32}{180}$

$\text{^0"C"="K} - 273.15$

""^0"F"= "K" times 9⁄5 − 459.67

Problem: what is 125 K in $\text{^0"C}$ and $\text{^0"F}$

125 K = $- 148.17$ $\text{^0"C}$
$= - 234.67$ $\text{^0"F}$